An Internet Protocol (Internet Protocol, IP) address is an identifier for identifying a user equipment or a network device, and is also an identifier used for IP packet forwarding in an IP network. Therefore, IP address assignment is essential to the entire IP network.
At present, the mode for assigning an IP address includes automatically obtaining an IP address. The mode for automatically obtaining an IP address is: a client may automatically obtain a host IP address, a gateway IP address, and a subnet mask on the network segment of the client, without human intervention. At present, the mainstream technology for automatically obtaining an IP address is the Dynamic Host Configuration Protocol (DHCP: Dynamic Host Configuration Protocol). In the technology, a DHCP server manages all IP network configuration data in a centralized manner, and is responsible for processing a DHCP request from the client. The client uses the IP configuration data assigned from the DHCP server.
During the implementation of the present invention, the inventor finds that the defect of automatically obtaining an IP address in the prior art is that: When a DHCP server and a client are not on the same network segment, a DHCP relay host needs to be configured on the same network segment of the client. The DHCP relay host receives a DHCP request from the client, sends the DHCP request to the DHCP server, and sends a response from the DHCP server to the client. However, generally, only a routing function is provided for a standard service of an IP network and an IP address automatic configuration function is not provided. The DHCP relay host function belongs to the IP address automatic configuration function rather than the routing function. Therefore, generally, the operator of a bearer network does not provide a DHCP Relay function. Since the operator of the bearer network does not provide the DHCP Relay function, IP address automatic configuration is difficult to be implemented when the IP network provides a standard service.